Will,
I too would recommend caution when using biological indicators as a guage of
soil toxicity.
Dr Jason Weeks of WRc - NSF in Marlow gave a paper in london last week, titled
"Current & emerging Ecotoxicological tests for contaminated land", where he
touched on topics such as earthworm bioassays, bio & lux biosensors being used
to provide site toxicity maps.
At the end of the paper, I specifically asked the question "so can we use
ecotox tests (i.e the bioluminescene tests) to give an indication on human
health risks?"
As far as i understood from the reply from both Paul Nathaniel and Jason, to
try to make the leap of faith from concentrations of contaminants which affect
eco receptors to concentrations to concentrations of contaminats that can
affect human health will place you on decidedly shakey ground. (pardon the pun)
As far as I understand, it is propably innappropriate to try and extrapolate
the results of what is effectively an ecotoxicity map to human health.
All that been said, the concept of the ecotox map allowing the investigator to
target areas for further intrusive investigations seems reasonable.
I have to caveat this reply by saying that this is only my understanding, and
please dont take this as Paul's or Jason's position. It is my interpretation
of the reply to my question, but anyone, please come back and comment.
Gerry McGarrity
______________________________________________
Gerry McGarrity
Contaminated Land Officer
Environmental & Consumer Protection Department
Dundee City Council
8 City Square
Dundee
DD1 3BG
Tel 01382 43 4038
Fax 01382 43 4080
mob 0789 987 3995
|